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GENERAL BIOLOGY 



bars of the wings of a night hawk, or the golden shafts of the 

 flicker, or the white side spots of a junco's tail, or the white 

 rump of a. rabbit, exposed only when the tail is lowered in 

 running, or the brilliant reds and blacks of the underwing 

 moths, etc., etc. These are suddenly flashed into view when 



FIG. 251 A carrion 

 red and black. 



their possessor takes flight, and as suddenly tucked away 

 again on alighting. They have been called "recognition 

 marks" on the assumption that they enable a fleeing herd of 

 gregarious animals of one species to keep together or help 

 individuals to find one another more readily. But it seems 



